Dynamik und Elementgehalte von Fichtenfeinwurzeln in Kalkgesteinsböden am Wank (Bayerische Kalkalpen)

Dynamics and nutrient concentration in fine-roots of alpine spruce stands on calcareous soils (Wank-Massif/Bavarian Alps) The dynamics and the concentrations of nutrient elements in the fine roots of two stands of alpine spruce differing in vigour on calcareous soils overlying limestone in the Wank massif of the bavarian alps were measured. Selected root parameters were compared with those obtaining on acid soils. At Wank, the concentration (mg/100 ml soil) of living fine roots and root tips was maximum in the organic surface layer and the mineral horizon immediately underlying the surface layer. There were significantly more fine root biomass (kg ha^?1) on the calcareous site (Walk) than on acid soils (Solling and Fichtelgebirge). There were also marked differences between the two sites in concentration of nutrient elements in the fine roots was strongly influenced by chemical composition of the soil solution.     

impact of high aluminium loading on a small catchment area (thuringia slate mining area) – geochemical transformations and hydrological transport

A field study was performed on the effects of acid mine leachate from slate mine tailings seeping into a small river passing through the tailings. Before entering the tailings the river water has high alkalinity which neutralizes acidity upon mixing with leachate within the tailings. Donwstreams of the tailings the pH of the river water ranges about pH = 8, the water contains high concentrations of sulfate (≈1500 μmol/1 and particulate bound aluminium (≈80 μmol/I), but low concentrations of dissolved aluminium (≈3 μmol/1). It is therefore assumed that AI(OH)₃ colloids are precipitated during the neutralisation process and transported out of the tailings. The concentration of particulate bound aluminium along the river shows a strong correlation with the concentration of sulfate, which indicates that particulate bound aluminium is conservative. It therefore seems that under dry weather conditions (under most of the sampling was performed) no chemical retention mechanism exists which confines the distribution of aluminium to a restricted part of the catchment area. In contrast, the white river sediment is rich in both aluminium and sulfate, which suggests the temporary formation of aluminium hydroxosulfate minerals. Favorable (i.e. acidic) conditions may prevail at high discharges where the acidity accumulated in the tailings is flushed into the river with its subsequent acidification.